反应详情

温度

85 °C

To a stirred solution of N-(5-bromo-4-chloropyridin-2-yl)acetamide (7 g, 28.1 mmol), 2,4,6-trivinyl-1,3,5,2,4,6-trioxatriborinane complex with pyridine (1:1) (8.78 g, 36.5 mmol), sodium carbonate (5.95 g, 56.1 mmol) solution in 7 mL of water and tetrakis(triphenylphosphine)palladium (0.973 g, 0.842 mmol) in a mixture of Toluene (50 mL) and Ethanol (8 mL), nitrogen gas was bubbled for 5 min. The reaction mixture was heated at 85° C. for 14 hours. After the completion, the reaction was diluted with EtOAc (50 mL), filtered through diatomaceous earth (Celite®). The filtrate was diluted with water and the organic layer was separated, washed with brine solution, dried over sodium sulfate. The organics were concentrated under reduced pressure and residue so obtained was purified by comb flash column 120 g using hexane/ethyl acetate. Product eluted at 30% EtOAc in hexane and required fractions were concentrated to yield N-(4-chloro-5-vinylpyridin-2-yl)acetamide (5.92 g, 27.7 mmol, 99% yield) as yellow solid. LC/MS (ESI) m/e 197.2 [(M+H)+, calcd for C9H10ClN2O 197.04] LC/MS retention time (method A): tR=1.50 min; 1H NMR (400 MHz, DMSO-d6) δ 10.79 (s, 1H), 8.64 (s, 1H), 8.18 (d, J=6.40 Hz, 1H), 6.88 (dd, J=11.20, 17.60 Hz, 1H), 5.99 (dd, J=0.80, 17.60 Hz, 1H), 5.47 (dd, J=0.80, 11.40 Hz, 1H), 2.12 (s, 3H).

1. customwas bubbled for 5 min
2. additionAfter the completion, the reaction was diluted with EtOAc (50 mL)
3. filtrationfiltered through diatomaceous earth (Celite®)
4. additionThe filtrate was diluted with water
5. customthe organic layer was separated
6. washwashed with brine solution
7. dry with materialdried over sodium sulfate
8. concentrationThe organics were concentrated under reduced pressure and residue
9. customso obtained
10. customwas purified by comb flash column 120 g
11. washProduct eluted at 30% EtOAc in hexane
12. concentrationrequired fractions were concentrated